FBI agents have raided the West Palm Beach, Fla. eye clinic owned by Dr. Salomon Melgen, the wealthy donor to New Jersey Democratic Sen. Bob Menendez who allegedly procured prostitutes for him – some of them as young as 16 – during trips to the Dominican Republic.

The Miami Herald reported that federal agents lined up vans outside the Melgen Eye Center late Tuesday night to haul away evidence in the case.

A woman answering the phone at Melgen’s home in West Palm Beach would not give her name but said, “Dr. Melgen is asleep.” Asked if he was aware his clinic was being raided by federal law enforcement, she replied, “Oh yes, well, these things happen all the time. They’ve got to do their job.” She declined to comment on Melgen’s relationship with Sen. Menendez.

Melgen, 58, is believed to have flown Menendez in his private jet to the Dominican Republic on several occasions for alcohol-fueled sex parties featuring prostitutes.

According to the Miami Herald, records obtained from the Palm Beach County recorder show Melgen also “has an outstanding IRS lien of $11.1 million for taxes owed from 2006 to 2009.”

It’s unknown whether the FBI is investigating his tax delinquency, his association with Sen. Menendez, or both. A spokesman for the FBI in Miami, Fla. would only say that the Bureau was “conducting law enforcement activity in the general vicinity of 2521 Metrocentre Blvd, West Palm Beach, FL” – the address of Melgen’s flagship clinic.

Menendez is slated to take over as chairman of the powerful Senate foreign affairs committee when Massachusetts Democratic Sen. John Kerry becomes secretary of state. The full Senate confirmed Kerry’s nomination on Tuesday.

But it’s unclear whether Senate Majority Leader Harry Reid will hand the committee’s gavel to Menendez without a full investigation into his conduct. Committee chairmen with jurisdiction over international matters typically have high-level security clearances. Menendez’s could be jeopardized if the allegations against him are proven true.

The Daily Caller first reported in November that two prostitutes had accused Menendez of paying them for sex during Easter weekend 2012 at a posh Dominican resort. Prostitution is legal in that country but viewed unfavorably by U.S. voters.

The women appeared in videotaped interviews with the help of a translator. Each said she was promised $500 to sleep with the New Jersey lawmaker, but was ultimately paid only $100.

On Jan. 25 TheDC followed up that reporting with new allegations contained in documents that a tipster placed online. Those files, published on a makeshift WordPress blog, have attracted nearly 20,000 online readers in the United States.

Among other claims, the documents indicated that the FBI was actively investigating the matter, and that some of the prostitutes Menendez slept with were younger than 18.

The PROTECT Act of 2003 made it a federal crime to pay for sex with anyone that young, regardless of the age of consent in the country where the illicit transaction occurs.

TheDC’s most recent reporting also raised the question of whether Menendez broke Senate Ethics committee rules by accepting free travel from Melgen without seeking the committee’s approval or disclosing the value of the perks.

On Monday afternoon, Menendez refused to address the substance of the allegations against him, telling TheDC only that he was “not going to respond to the fallacious allegations of your story.”

One day later, Senate Majority Leader Harry Reid took a swing at The Daily Caller for its reporting, telling assembled journalists Tuesday that “I always consider the source” of allegations, “and all anyone here has to look at is the source where this comes from. It’s – it’s a source that has brought up a lot of non-issues.”

Spokespersons for Sens. Reid and Menendez did not immediately respond to late-night emailed requests for comment.